An extensive clinical resource comprised of eight well documented families which manifest the cancer family syndrome, as well as an additional ten to fifteen lesser evaluated cancer prone families which may constitute the syndrome are presently being investigated. The resource has been under study for many decades by numerous investigators. In the case of Family G, more than 75 years of work including Warthin's original studies, those of his colleagues Hauser and Weller, and since 1965 those of our own group have gone into its assembly and follow-up. The resource can be maintained through the modest funding requested which could provide the necessary field personnel (two registered nurses, and a secretary), so that key relatives can continue to be contacted and rapport with each of the families can be maintained at the highest possible degree to guarantee continuous updating of the genealogies with medical and demographic data, and especially tumor verification. The unique aspect of the resource rests upon the fact that the vertical transmission of cancer, with segregation in its occurrence consistent with a mendelian autosomal dominant factor in several of the families, permits careful delineation of high and low risk cancer prone lineages so that genetic-environmental issues can be critically scrutinized. Thus, the potential for comprehension of carcinogenesis is maximized. Finally, this resource could serve as an excellent model for cancer control, a problem already under investigation in this proposal. Future investigations of the resource for specific biological factors including potential genetic markers are in the planning stage. Extensive pathologic investigations will also begin through the collaboration of pathologists from two medical centers and this will not involve any additional cost to the grant.